i don't get it what you really mean. you're asking if you have to do these steps while you're installing gentoo?

of course! where would you otherwise store you data? on floppys? no!
all three steps are necessary to have a fully functional gentoo system. without the "-j" param mke2fs builds an ext2 fs for example.

i don't get it what you really mean. you're asking if you have to do these steps while you're installing gentoo?

Yes, but I meant only on that particular partition marked as "Whole Disk".
Probably I didn't make myself clear enough, I'm sorry.
says I have only 1 hdd, /dev/hda
I partitioned it into /dev/hda1, /dev/hda2, /dev/hda3, /dev/hda4,
while installing on SPARC, it's required that there is a partition "whole disk", as in the handbook (/dev/hda3 for example.), but all of the hda1, hda2, hda4...etc are on the same drive, just different partition so I can make different file system on each partition, correct?
if hda3 is the "whole disk", does it mean that if I did mke2fs /dev/hda3, it will overwrite what I have done, says mkreiserfs /dev/hda4, since hda4 is *part of* the "whole disk"???

The file system is on /dev/sdc1, and /dev/sdc3 is there as part of the sun
label. You will notice that they are both the "whole disk," so that if I
actually built a file system on /dev/sdc3, there would be an empty file
system (or garbage) on both partitions.

Sorry to go on so long, but you really don't want to mess with the whole
disk partitions.

If that's the case, I think the Gentoo handbook should clarify this for SPARC users, since in the handbook, it follows the x86 arch. and use /dev/hda3 as the root partition, but in SPARC section, /dev/hda3 happened to be the "whole disk" partition, if users follow the instruction, after partition the hdd, users would tend to do mke2fs -j /dev/hda3 (I did that once), which is incorrect for Sun Dish Label.

Doesn't want to fix? I've separated and fixed (as you so kindly say it) the handbook sunday, drafts are available on http://www.gentoo.org/doc/en/handbook/draft/handbook-sparc.xml?part=1 and most architectures will have these instructions official before the end of the week. Only sparc will lag a bit behind because I am waiting for better fdisk instructions you promised me :p